With Astoria workbench, if you check out a document to the Editor and get the WebDAV URL instead of the doc, this is usually one of two issues:
1. The WAN bridge to Arbortext isn't installed - check add/remove programs
2. The astoriawanbridge.acl file isn't being read in by the Arbortext Editor on startup.
The best way to check the second one is turn on the command line for the editor from your preferences, and type "eval package_file(menus)" and this should return a pathname to this file located in a custom\init directory. If it returns nothing, there's your issue.